Doom 2

Idkfa gives you all guns, ammo and keys
iddqd gives you God mode
idclip makes you able to walk through walls
idbehold gives number of options,
idchoppers gives chainsaw hold tab type
iddt twice for level maps and location of monsters once you double click on the doom II icon hod down comand and m this puts you into the network screen

idclevxx (x =level number) for level select
idbeholdl to brighten the game tempararely
iddqd GOD MODE !
idkfa all guns with full ammo and all keys TO GET
ALL WEAPONS PUT THIS CODE IN(IDKFA)
TO WALK THROW WALLS PUT IN (IDCLIP)
TO GET LIFE UP PUT IN (IDDQD) In Doom2 the 1st
level has a glich where when you do
idkfa and swich to the chanesaw all the sargents
have wings try it!!

When you get to the end of the Wolfenstein level, before you open
the door to the final door enable the idclip code. Looking at the
door, go into the right wall. Search around until you get to a room
with another exit. Click the exit button in that room to go to a
different screen with the message "You have found the super secret
level. You should fly through this one." It says this because there
is a Cyber Demon ahead.

When you enter the room with the large window, look along the left
wall until you get to a switch. Hit the switch then get on the
platform and wait for it to rise. Kill any enemies in your way.
Now, click the "Open Door" button on the wall you are now facing.
The wall should open. Again, clear out any enemies in your way. Go
the the far end of that passageway and look toward the room. Hold
[Sprint ] and run off the platform and onto the lighted square. You
should hear the faint noise of a door opening. Go to the room where
the blue life jars were located. The door in the back of that room
should have opened up to reveal a rocket launcher.

In the last level, Icon Of Sin, there is a giant face that keeps
launching "boxes" through a hole in his forehead. You must activate
the platform. Take the invulnerability just in case, and while going
up, aim with the rocket launcher at the correct moment so that the
rocket goes through the hole from where the boxes appear from.
Repeat this as many times as needed.

Type t in the map to enter talk mode. Hold [Alt ] and type iddt
several times. This will reveal the entire map. Repeat the code to
reveal all items. Repeating the code again will return the map to
normal.

Start the game with the doom -devparm
command line to activate the listed cheat function. *** The
parameters marked with an asterisk (*) do not require -devparm in
the command line. Most of these parameters can be mixed and matched
to create different effects. For example, start the game with the
doom -devparm -wart 1 8 -record demo01 -respawn command line would
record a demo on episode one, level eight, with monster respawn.
Finally, press [F1] during development mode for a 256 color
screenshot in .PCX format.

Go to level 30, Icon Of Sin. Collect all the items, then enable the
iddqd code. Go through the warp, then enable the idclip code. Go
backwards until you get to the skull switch. Blast the demon that
appears with 2 rockets to kill it. Activate the switch. Go on the
rising platform using the idclip code. Do not walk through the wall
of the demon. Blast the demon's forehead (the part that makes skull
boxes). This will hit the head on a stick inside. You should be able
to hear a roar. The rocket box on top of the platform can be
collected an unlimited number of times, unless you collected the box
beforehand.

Near the end of level 30 when there are no monsters, the face still
shoots out monsters. Enable the idclip code and go through the same
wall as "boxes" are going through. Either save your game or enable
the iddqd code. There are thousands of monsters to kill.